Hydraulic dredge



Dec. 10, 1935. A 1 KERTZMAN 2,023,686

l HYDRAULIC vDREDGE Filed May l5, 1955 asf,

. Mom/m30 Patented Dec. 1o, 193s UNITED STATES PATENT ,OFFICE HYDRAULIC DREDGE Albert J. `Kertzman, Winona, Minn.

Application May 13, 1935, Serial No. 21,126

6 Claims.

In the recovery of subaqueous sand and gravel, it is frequently desirable to separate the ner from the coarser material and this is usually done as a second operation after the dredging opera- 5 tion. To eliminate this second operation and the attendant expense, I have devised the dredge described and claimed in my Patent No. 1,964,951, dated July 3, 1934, which is adapted to separate much of the coarser from the finer material during the dredging operation. The present invention relates to improvements in mechanism of lthat type having a separator screen located in the dredging head and particularly to remote controlling mechanism for the suction in the dredging head compartments.

It is an object of this invention to provide simple and eicient means operable during the dredging for controlling the separation of the coarser from the ner material in the head of an ii) hydraulic dredge.

A further object is to provide novel means for quickly and automatically removing obstructing matter from a screen in the dredging head.

Other objects will appear and be more fully pointed out in the following specification and claims.

Referring to the drawing:

Figure 1 is a diagrammatic side elevation of my improved dredge;

Fig. 2 is a cross section taken on the line 2-2 of Fig. 1; A

Fig. 3 is a longitudinal section through the dredging head and connections with a modified form of suction control, and :3.3 Fig. 4 is a sectional view through the valve for the remote controlling mechanism.

Referring to Fig. 1 of the drawing, the numeral 5 indicates diagrammatically a barge carrying dredging mechanism of the hydraulic type. This 40 mechanism includes centrifugal. pumps 6 and 'l having discharge conduits 8 and 9 respectively adapted to conduct the dredged material to suitable places of deposit. A dredge pipe I has a flexible'connection I I with the pump 6 and secured on the intake end of the pipe I0 is a dredging head indicated generally by the numeral I2.

This head is open at its side I3 andan upper chamber 4 is barred from the open side I3 by a `screen I of wire mesh of suitable gaugeto allow the passage of the finer material or sand into the chamber |4 from which it is Withdrawn through a pipe I6 connected to the intake pipe of the pump 1 through a flexible section Il.

Mechanism of the usual or suitable type is provided for moving the head I2 against the material 31 to be excavated. As shown in Fig. 1, operating means for the head I2 include a cable I8 running on a sheave I9 secured to the pipes I0 and I6.

As shown in Figs. 2 and 3, the passage of ex- 5 cessively large objects into the pipe I0 is barred by an arcuate arm rigidly mounted on the inner wall of the head I2 and projecting halfway across the mouth of the pipe I0.

Communicating with the chamber I4 is a by- 10 pass 2| under remote control to permit the regulation of the suction or pressure in the chamber 4. As shown in Figs. 1 and 2, a flexible closure 22 is arranged to extend across the by-pass 2|. This closure is secured at its periphery to the bct- 15 tom of a bell-shaped casing 23. The top of the casing 23 is connected by a pipe 24 to a valve 25 conveniently located on the barge `5. 'Ihe casing 23 and the flexible closure 22 are spaced from the top of the head I2 so that when the closure 20 22 is drawn away from its seat on the by-pass 2|, as indicated in dotted lines in Fig. 2, water is admitted to the by-pass. As shown in Figs. 1 and 4, the valve 25 has a handle 26 for turning a closure member 2l to such positions as to place 25 the pipe 24 in communication either with a pressure pipe 28 extending to a pump 29 or with a suction pipe 30 communicating With the intake of the pump 6. The closure member 21 may also be moved to such a position as to close the 30 pipe 24 entirely.

In the alternate form of by-pass control shown in Fig. 3, a cylinder 3| is substituted for the casing 23 vand is placed in communication with the valve 25 through a nipple 32 joined to the pipe` 24. 35

Within the cylinder 3| a piston 33 is movable and is connected by a rod 34 to a closure 35 for the bY-paSs 2| The cylinder 3| is secured to the top of the head I2 and spaced therefrom by brackets 36.

Operation In operation the subaqueous material 3l is excavated hydraulically, both of the pumps 6 and 1 being continuously operated so that suction is created in the head I2 both in the lower or intake chamber and in the chamber I4. The coarser material is carried by the pipe I0 to the pump 6 and is discharged through the pipe 8 at a suitable place of disposal. Simultaneously with this operation, much of the ner material is drawn through the screen |5 into the chamber I4 and is carried through the pipe I6, pump 1 and pipe 9 to a separate place of disposal.

As the proportion of the coarse and fine material varies between side limits, it is sometimes desirable to partially open the by-pass 2| and thereby reduce the suction in the chamber I4 and correspondingly reduce the proportion of finermaterial drawn through the screen I5 into the pipe I5. The opening of the by-pass closure is controlled by the remote valve 25, the handle 26 of which is positioned by the operator so as to place pipe 24 in communication with the suction pipe 3|] and thereby open the by-pass the desired degree. When the by-pass is to be closed, the member 21 is moved to such position as to place the pipe 24 in communication with the pipe 28 connected to the pump 29. Either water, air or other fluid may thus be forced into the casing 23 or cylinder 3|.

With the form of closure shown in Figs. 1 and 2, the pump 2.9 may be eliminated, atmospheric pressure, ordinarily, being suficient to close the member 22.K Because of the friction of the piston 33 in the cylinder 3|, however, I prefer to employ the pump 29 to positively close the member 35 under control of the Valve 25. When',as sometimes occurs,the screen I5 becomes clogged, the obstructing material may be cleared away by opening the by-pass to its fullest extent momentarily. This results in reversing the iiow of water through the screen I5 so that the obstructing material is drawn off through the pipe I'IJ without interruption of the operation of the dredge. The diameter of the by-pass 2| is` preferably greater than that of the opening through the pipe I6 and the area of the closure 22 exposed to the suction of the casing 23 is substantially larger than the by pass cross sectional arca. Similarly the head of the piston 3 3 is greater than the area of the closure 35 exposed to the suction in the by-pass It will be understood that the relative sizes of the pipes I and I6 may be varied between wide limits and in some cases, such as where it is desired to separate and recover a maximum of the ne` material, the pipe I 6 may be made larger than the pipe IIJ and pumps of proportionate capacity may be severally connected to these' pipes,

.without departing from the spirit of my invention.

The form of the dredging head I2 may also be varied'between wide limits to meet the varying conditions of the subaqueous soil and the usual or suitable attachments, such as rotary or other movable excavating mechanism, may be used in connection with my improved dredge.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A dredge having in combination, an' intake head, a plurality of conduits for excavated m'aterial communicating with said head, means in said head adapted to bar the passage of the coarser material to one of said conduits and allowing the passage of the finer material thereto, means for creating suction in both of said conduits, a by-pass communicating with said head, l a closure for said by-pass and means for actuating said closure from a station of an operator remote therefrom.

2. An hydraulic dredge having in combination, an intake head, a plurality of conduits for excavated material communicating with said head, a

`terial to one of said conduits and allowing the passage of the ner material thereto, means for creating suction in both of said conduits, a bypass communicating with the delivery side of said screen, a closure for'saidby-pass, pressure coni. trolled operating mechanism for said closure and a valve operable from a position remote from said 25 head and controlling said mechanism for operating said closure.

4. In an hydraulic. dredge, an intake head, a screen dividing said head into a plurality of chambers, a dredge pipe communicating with each of said chambers, means for creating suctionin said pipes, a by-pass communicating with one of said chambers, a closure for said by-pass and means for actuating said closure to and from closed position from a station remote from said head.

5. In an hydraulic dredge, an intake head, a screen dividing said headk into a plurality of chambers, va dredge pipe communicating with' each of said chambers, means for creating suction in said pipes, a by-pass communicating with the 40 delivery side of said screen and so proportioned relative to said pipes as to permit the reversal of flow through said screen, a closure' for said bypass, and means for regulating the degree of opening of said closure from a point remote from said head.

6. In an hydraulic dredge, an intake head, a screen dividing said head into an upper and a lower chamber, said screen being formed and arranged to permit the passage of the iiner exca-,O Vated material only into said upper chamber, a

-dredge pipe communicating with each of said chambers, means for creating suction in both of said pipes, a by-,pass communicating with said upper chamber and having a `cross sectional area greater than the passage through the dredge pipe communicating with said upper chamber, a closure for said by-pass and'means for actuating said closure from a position remote from said head. 60

ALERT J. KER'IZMAN. 

